In the prior arts and states of technologies, electrical power generation as well as Combined Heat and Power (CHP) has been known to employ a relatively uniform and small sized Biomass fuel source (saw dust, wood chips, pellets, etc . . . ) in a thermodynamic cycle. In the current art and state of technology, direct combustion systems will burn consistent, uniform and relatively small fractionalized biomass as fuel in a “Boiler” to produce steam that is expanded in a Rankine Cycle prime mover to produce power. Cofiring is also known to substitute biomass for coal or other fossil fuels in existing coal-fired boilers. In all cases (excluding the present Invention and all the matters related thereto disclosed herein), various forms of parasitic energy consuming processes perform “Homogenization” or the process by which Biomass feedstock is made physically uniform for further processing and combustion which commonly includes chopping, shredding, grinding, chipping, and pelletizing, etc . . . is deployed. Similarly, “Communition” or the process in which solid materials are reduced in size, by crushing, grinding and other procedures is a like term sometimes used to described Biomass fractionalization.
The present Invention encompasses use of all phases and/or states of working fluids (which may include subcritical, supercritical, and ultra-supercritical) to create Bioenergy in both independent and/or individual application(s) as well as an array of inter-dependent, cascading, and/or bottom cycling combination(s) of the aforementioned cycles mentioned above. Such array(s) purpose(s) may be to optimize the present Invention's overall systemic efficiencies and/or provide multiplicities of differing forms of Non-To-Minimally Fractionalized Biomass-Fueled renewable energy; which may additionally include the production of Biofuels using the Invention's systemic production of heat, power and mechanical energy.
Although the present Invention falls within the noted Fields of Invention as previously identified, the Inventor hereof does disclose that, to the best of his knowledge and belief, no such specialized prior art of “Non-To-Minimally-Fractionalized Biomass-Fueled Renewable Energy” exists; except for that which has been presented by the Inventor hereof himself. Such presentations are further identified in those hereof, demonstrated by Inventor's working prototype described herein, and disclosed hereby in the present Invention.
The present Invention's distinction from the prior arts are further delineated in that the present Invention and those Patent Applications (identified hereof) utilize Biomass, in its “Non-To-Minimally Fractionalized” form, whereby no costly chipping, grinding, etc . . . (Homogenization and/or Comminution) is necessary. It should be noted that those skilled in the art and state of technology have steadfastly rejected Inventor's conception and standpoint that a highly inconsistent Biomass fuel source, explicitly “Non-To-Minimally Fractionalized Biomass”, could be utilized to produce precise and useful renewable electricity and/or concluded that such would not be feasible. Nonetheless, the Inventor hereof persevered over years and proved dismissing pronouncements both incorrect and ill-founded. Therefore, the Inventor does hereby respectfully state “a new, novel, and specialized art and state of technology”, i.e. “Non-To-Minimally Fractionalized Biomass-Fuel Renewable Energy” appears to have been created by Inventor hereof and is further presented hereby.
To additionally clarify, it is hereby noted that the present Invention of “Non-To-Minimally Fractionalized Biomass-Fueled Renewable Energy” as well as the disclosures pursuant, specifically including the described working prototype (believed to be the World's first and only such system of its type), are inescapably linked via the commonality of their original and inventive conversion of “Non-To-Minimally Fractionalized Biomass” to Bioenergy; such having originated by and through the same sole Inventor and the Applicant hereof.
More specifically, however not limited to, the present Invention deploys a Non-To-Minimally Fractionalized Biomass-Fueled modified Rankine Cycle, utilizing “R744” (one of the oldest known, natural, and ecologically benign refrigerants) a/k/a Carbon Dioxide (CO2) as the working fluid, in a Supercritical Power Generation Cycle for the production of renewable electricity. Via use of the present Invention's novel Biomass Combustion Unit, substantial portions of the thermal energy derived from high temperature (greater than 1,500° F.) and complete combustion of Non-To-Minimally Fractionalized Biomass fuel is exploited for direct flue gas heating of the R744 or CO2 working fluid which is expanded to provide high pressurized energy driving a turbine or other like device connected to an electrical generator. The present Invention additionally provides for portions of the Heat Energy generated from its innovative Biomass Combustion Unit's water cooled Burn Box to operate a codependent Subcritical Power Generation Cycle. The Subcritical Power Generation Cycle uses simple hot water as an intermediate medium of heat exchange in thermal communication with its eco-friendly refrigerant “R245FA” working fluid in an Organic Rankine Cycle. Further offered by the present Invention is an array of other useful purposes provided by Non-To-Minimally Fractionalized Biomass heat energy as described herein.
Fractionalized Biomass in the form of wood chips, saw dust, and other uniform and consistent small sizes have been well known to fuel various types of “Boilers” to operate steam turbines in Combined Heat and Power (CHP) applications for over a century. However, such art and state of technology differs greatly and significantly from the present Invention, explicitly in that no steam is utilized nor is any consistently uniform small sized Biomass necessary.
Small scale “Log Boilers” (typically outputting less than 10 mm/btu/hr), of the type manufactured by the companies known as Log Boiler Canada, manufactured in Canada and TLB, Inc., located in Hudsonville, Mich., have likewise been believed marketed for the purposes of providing non-pressurized (open loop) hot water (typically at less than 200° F.) for routine and varying heating operations and may be useful for smaller scale cyclic heating applications. Such “Log Boilers” have been designed to a varying heat load and thus reactionary based upon the heating requirements of changing climatic conditions. Therefore, they generally simply cycle input combustion air to maintain a “fire” in their combustion chamber. Such “fire”, particularly during periods of reduced or stopped input combustion air, is often “smoldering” and exhausts pollutants resulting from Biomass incomplete combustion.
“Air Curtain Incinerators”, of the type manufactured by Air Burners, Inc. in Palm City, Fla., are well advanced, commercially available, and well known for use in the incineration of a wide range of Biomass. Such are typically skid-mounted and used as both permanent (stationary) units at landfills or transfer stations and as portable units in the land clearing or forest industries. Air Curtain Incinerators have no top enclosure and are often placed temporarily in natural disaster sites to aid in the riddance and cleanup of Biomass debris.
Problems with the fractionalization of Biomass for use as a fuel source are notorious, quite numerous, and specifically include, however are not limited to: (i) high capitalization cost of fractionalizing equipment, i.e. wood chippers, tub grinders and the like, (ii) very high operational and maintenance costs intrinsic to the operation of the fractionalization and/or subsequent recompression equipment (pelletizing and/or briquetting machines), (iii) vast amounts of parasitic energy (often fossil diesel fuel) required in fractionalization and/or subsequent recompression (generally using vast amounts of electricity), (iv) fractionalization equipment's fossil fueled combustion engine pollution, (v) problematic associated airborne fugitive particular matter resulting from chipping and/or grinding operations, (vi) expensive, redundant, and complex handling procedures of wood chips and the like related to the required equipment that must be utilized, (vii) high capitalization cost storage facilities, (viii) shortened “shelf live” and Biomass BTU energy content losses via the fractionalized Biomass susceptibility to the naturally occurring composting process, (ix) costly turning over (rotation) of stored wood chips piles to prevent composting and related heat generation resultant therefrom, and (x) the common, inherent, and well documented risks, occurrences, and costs of wood chip fires and associated firefighting. The host of the above identified problems serving to dramatically increase the cost of Biomass fuel; for example, pelletizing may increase per ton costs by as much as 20 times that of Non-To-Minimally Fractionalized Biomass.
Many thermodynamic cycles include well established and commercially available “Boilers” used for the production of pressurized steam. In the current art and state of technology Boilers using wood chips feature relatively delicate refractory (thermal ceramics, fire bricks, and the like) for heat retention and steel protection and are coupled with particular system types commonly known as: (i) Heat Recovery Steam Generators—using water as the working fluid, (ii) “Heat-To-Power Generators” deploying Organic Rankine Cycles which may utilize a host of organic working fluids; particularly including refrigerants such as R245FA, and (iii) Rankine Cycle, Regenerative Rankine Cycle and modified Rankine Cycle(s), and the like which may deploy water (steam), refrigerants, as well as a host of other organic and/or inorganic working fluids and/or combinations of such working fluids. These thermodynamic cycles are known to have produced electrical power generation, CHP, and CCHP using energy provided by the combustion of a fuel. These cycles may be further described as a recurring cycle of four constituent processes. In one process, their respective working fluids are pumped from a low pressure to a high pressure. In a second process, the liquid working fluids are heated at substantially constant pressure to become a vapor. In a third process, the vapor is expanded through a turbine coupled to an electric generator for power production while concomitantly decreasing its temperature and pressure. In a fourth process, the vapor is condensed to become a liquid.
For example U.S. Pat. No. 5,704,209 to Bronicke et al. discloses an externally fired combined cycle gas turbine system have a compressor for compressing ambient air, a water heat exchanger for heating the compressed air, an air turbine for expanding the heated compressed air in the generator connect to the turbine for generating electricity. The system also includes a source of energy such as solar energy, oil shale, solid waste fuel, landfill gas, biomass or combinations thereof and/or hydrocarbon fuels for adding heat to the compressed air in the air heat exchanger and producing heat depleted gases exiting the heat exchanger. The system further includes a closed Rankine cycle power plant having a water heat exchanger for vaporizing water and producing steam using heat contained in the heat depleted gases and steam turbine for expanding the steam and producing power and expanded steam.
U.S. Pat. No. 7,882,692 to Pronske et al. discloses a fuel combustion power generation system operating a closed Rankine cycle with a working fluid that is externally heated by combustion of fuel in the presence of oxygen in a combustor. Products of the combustion, typically including steam and CO2, are routed through a high temperature side of a heat exchanger through whose low temperature side passes the working fluid of the closed Rankine cycle. The working fluid is passed on to a turbine, or other expander, which in turn is coupled to generator for a.c. electrical power generation. The fuel may be solid, liquid, or gaseous fuel, such as coal or biomass, but gasification before combustion is disclosed.
Maxxtec AG of Sinsheim, Germany offers Organic Rankine Cycle modules in which combustion of fractionalized biomass produces combustion gases at temperatures of approximately 1,700° F. which, via a heat exchanger, heats thermal oil to a temperature of around 570° F. to 625° F. A secondary circuit having a second heat exchanger uses the thermal oil to heat organic fluid for the Organic Rankine Cycle. The heated organic fluid is evaporated in a turbine and drives the turbine to generate electricity by way of a generator to which the turbine is mechanically coupled. Water cooled condenser(s) condense the organic vapor and heated cooling water is available for use for various heating applications such as heating dryers or hot water heating systems. Although solid wood biomass may be used as fuel, such must be chipped, shredded or otherwise fractionalized into small, substantially uniform pieces prior to combustion.
In US Patent Application 20110061384, Filed on Sep. 13, 2010 and published on Mar. 17, 2011, entitled: HEAT ENGINE AND HEAT TO ELECTRICITY SYSTEMS AND METHODS WITH WORKING FLUID FILL SYSTEM (believed by Applicant to have been subsequently assigned to Echogen Power Systems, Inc. with certain license and exclusive market rights to the technologies and intellectual property having been later acquired by Dresser-Rand Group, Inc.), a method of utilizing Carbon Dioxide (CO2) as a working fluid in a thermodynamic cycle is disclosed. Such believed by Applicant to be additionally known as the Thermafficient® thermal engine. In such Invention a waste heat exchanger is described in thermal communication with a waste heat source for the production of electricity. Further reference to a specific related document is entitled: